This invention relates to electric devices which are connected in an electric circuit by plug-in electric connectors which attach to the terminals of the device. Plug-in connectors which are part of an electrical wiring harness such as for vehicle application, are often keyed to insure that the respective wires of the harness are connected to the proper device. In certain instances, the same electrical device may be used in a plurality of applications, the only difference being a requirement for different keying at the plug-in connector body of the device. If the connector body is an integral part of the molded housing of the device, such requirement for different keying in the connector body requires a different device housing and therefore, a different device.